Silicon iron alloys have excellent soft magnetic properties, and have been much used as magnetic cores of electric transformers or material for other electric devices. It is known that the more Si content, the more improved are the soft magnetic properties, and these properties show peaks at around 6.5 wt %. However, if Si content were more than 4.0 wt %, an elongation would be rapidly decreased, and ordinary cold rolling could not be practiced. Therefore it has been regarded as impossible to industrially produce sheet containing Si of more than 4 wt %.
This invention has been developed in view of such circumstances, and is to provide a method of effectively producing high silicon iron sheets of more than 4 wt % Si via the rolling processes.